import { HeaderBar } from '@/components/ui/HeaderBar';
import { Colors } from '@/constants/Colors';
import { useAppDispatch, useAppSelector } from '@/hooks/redux';
import { useColorScheme } from '@/hooks/useColorScheme';
import type { CheckinExercise } from '@/store/checkinSlice';
import { getDailyCheckins, removeExercise, setCurrentDate, syncCheckin, toggleExerciseCompleted } from '@/store/checkinSlice';
import { Ionicons } from '@expo/vector-icons';
import { useFocusEffect } from '@react-navigation/native';
import { useRouter } from 'expo-router';
import React, { useEffect, useMemo } from 'react';
import { Alert, FlatList, SafeAreaView, StyleSheet, Text, TouchableOpacity, View } from 'react-native';

function formatDate(d: Date) {
  const y = d.getFullYear();
  const m = `${d.getMonth() + 1}`.padStart(2, '0');
  const day = `${d.getDate()}`.padStart(2, '0');
  return `${y}-${m}-${day}`;
}

export default function CheckinHome() {
  const dispatch = useAppDispatch();
  const router = useRouter();
  const today = useMemo(() => formatDate(new Date()), []);
  const checkin = useAppSelector((s) => (s as any).checkin);
  const record = checkin?.byDate?.[today];
  const theme = (useColorScheme() ?? 'light') as 'light' | 'dark';
  const colorTokens = Colors[theme];

  useEffect(() => {
    dispatch(setCurrentDate(today));
    // 进入页面立即从后端获取当天打卡列表，回填本地
    dispatch(getDailyCheckins(today)).unwrap().catch((err: any) => {
      Alert.alert('获取打卡失败', err?.message || '请稍后重试');
    });
  }, [dispatch, today]);

  useFocusEffect(
    React.useCallback(() => {
      // 返回本页时确保与后端同步（若本地有内容则上报，后台 upsert）
      if (record?.items && Array.isArray(record.items)) {
        dispatch(syncCheckin({ date: today, items: record.items as CheckinExercise[], note: record?.note }));
      }
      return () => { };
    }, [dispatch, today, record?.items])
  );

  return (
    <SafeAreaView style={[styles.safeArea, { backgroundColor: theme === 'light' ? colorTokens.pageBackgroundEmphasis : colorTokens.background }]}>
      <View style={[styles.container, { backgroundColor: theme === 'light' ? colorTokens.pageBackgroundEmphasis : colorTokens.background }]}>
        <View pointerEvents="none" style={styles.bgOrnaments}>
          <View style={[styles.blob, { backgroundColor: colorTokens.ornamentPrimary, top: -60, right: -60 }]} />
          <View style={[styles.blob, { backgroundColor: colorTokens.ornamentAccent, bottom: -70, left: -70 }]} />
        </View>

        <HeaderBar title="今日打卡" onBack={() => router.back()} withSafeTop={false} transparent />
        <View style={[styles.hero, { backgroundColor: colorTokens.heroSurfaceTint }]}>
          <Text style={[styles.title, { color: colorTokens.text }]}>{today}</Text>
          <Text style={[styles.subtitle, { color: colorTokens.textMuted }]}>请选择动作并记录完成情况</Text>
        </View>

        <View style={styles.actionRow}>
          <TouchableOpacity style={[styles.primaryBtn, { backgroundColor: colorTokens.primary }]} onPress={() => router.push('/checkin/select')}>
            <Text style={[styles.primaryBtnText, { color: colorTokens.onPrimary }]}>新增动作</Text>
          </TouchableOpacity>
        </View>

        <FlatList
          data={record?.items || []}
          keyExtractor={(item) => item.key}
          contentContainerStyle={{ paddingHorizontal: 20, paddingBottom: 20 }}
          ListEmptyComponent={
            <View style={[styles.emptyBox, { backgroundColor: colorTokens.card }]}>
              <Text style={[styles.emptyText, { color: colorTokens.textMuted }]}>还没有选择任何动作，点击“新增动作”开始吧。</Text>
            </View>
          }
          renderItem={({ item }) => (
            <View style={[styles.card, { backgroundColor: colorTokens.card }]}>
              <View style={{ flex: 1 }}>
                <Text style={[styles.cardTitle, { color: colorTokens.text }]}>{item.name}</Text>
                <Text style={[styles.cardMeta, { color: colorTokens.textMuted }]}>{item.category}</Text>
                <Text style={[styles.cardMeta, { color: colorTokens.textMuted }]}>组数 {item.sets}{item.reps ? ` · 每组 ${item.reps} 次` : ''}{item.durationSec ? ` · 每组 ${item.durationSec}s` : ''}</Text>
              </View>
              <TouchableOpacity
                accessibilityRole="button"
                accessibilityLabel={item.completed ? '已完成，点击取消完成' : '未完成，点击标记完成'}
                style={styles.doneIconBtn}
                onPress={() => {
                  dispatch(toggleExerciseCompleted({ date: today, key: item.key }));
                  const nextItems: CheckinExercise[] = (record?.items || []).map((it: CheckinExercise) =>
                    it.key === item.key ? { ...it, completed: !it.completed } : it
                  );
                  dispatch(syncCheckin({ date: today, items: nextItems, note: record?.note }));
                }}
                hitSlop={{ top: 6, bottom: 6, left: 6, right: 6 }}
              >
                <Ionicons
                  name={item.completed ? 'checkmark-circle' : 'checkmark-circle-outline'}
                  size={24}
                  color={item.completed ? colorTokens.primary : colorTokens.textMuted}
                />
              </TouchableOpacity>
              <TouchableOpacity
                style={[styles.removeBtn, { backgroundColor: colorTokens.border }]}
                onPress={() =>
                  Alert.alert('确认移除', '确定要移除该动作吗？', [
                    { text: '取消', style: 'cancel' },
                    {
                      text: '移除',
                      style: 'destructive',
                      onPress: () => {
                        dispatch(removeExercise({ date: today, key: item.key }));
                        const nextItems: CheckinExercise[] = (record?.items || []).filter((it: CheckinExercise) => it.key !== item.key);
                        dispatch(syncCheckin({ date: today, items: nextItems, note: record?.note }));
                      },
                    },
                  ])
                }
              >
                <Text style={[styles.removeBtnText, { color: colorTokens.text }]}>移除</Text>
              </TouchableOpacity>
            </View>
          )}
        />
      </View>
    </SafeAreaView>
  );
}

const styles = StyleSheet.create({
  safeArea: { flex: 1, backgroundColor: '#F7F8FA' },
  container: { flex: 1, backgroundColor: '#F7F8FA' },
  header: { paddingHorizontal: 20, paddingTop: 12, paddingBottom: 8 },
  headerRow: { flexDirection: 'row', alignItems: 'center', justifyContent: 'space-between', zIndex: 2 },
  backButton: { width: 32, height: 32, borderRadius: 16, alignItems: 'center', justifyContent: 'center', backgroundColor: '#E5E7EB' },
  hero: { backgroundColor: 'rgba(187,242,70,0.18)', borderRadius: 16, padding: 14 },
  title: { fontSize: 24, fontWeight: '800', color: '#111827' },
  subtitle: { marginTop: 6, fontSize: 12, color: '#6B7280' },
  bgOrnaments: { position: 'absolute', left: 0, right: 0, top: 0, bottom: 0 },
  blob: { position: 'absolute', width: 260, height: 260, borderRadius: 999 },
  blobPrimary: { backgroundColor: '#00000000' },
  blobPurple: { backgroundColor: '#00000000' },
  actionRow: { paddingHorizontal: 20, marginTop: 8 },
  primaryBtn: { backgroundColor: '#111827', paddingVertical: 10, borderRadius: 10, alignItems: 'center' },
  primaryBtnText: { color: '#FFFFFF', fontWeight: '800' },
  emptyBox: { marginTop: 16, backgroundColor: '#FFFFFF', borderRadius: 16, padding: 16, marginHorizontal: 0 },
  emptyText: { color: '#6B7280' },
  card: { marginTop: 12, marginHorizontal: 0, backgroundColor: '#FFFFFF', borderRadius: 16, padding: 16, flexDirection: 'row', alignItems: 'center', gap: 12, shadowColor: '#000', shadowOpacity: 0.06, shadowRadius: 12, shadowOffset: { width: 0, height: 6 }, elevation: 3 },
  cardTitle: { fontSize: 16, fontWeight: '800', color: '#111827' },
  cardMeta: { marginTop: 4, fontSize: 12, color: '#6B7280' },
  removeBtn: { backgroundColor: '#F3F4F6', paddingHorizontal: 10, paddingVertical: 6, borderRadius: 8 },
  removeBtnText: { color: '#111827', fontWeight: '700' },
  doneIconBtn: { paddingHorizontal: 4, paddingVertical: 4, borderRadius: 16, marginRight: 8 },

});